The federal opposition is getting behind the controversial Cross River Rail (CRR) plan, pledging $2.24 billion for the project if the Labor party takes office at the next election.

The proposed passenger rail line will cover the 10.2 kilometre north-south stretch between Bowen Hills to Dutton Park. It will also require almost six kilometres of tunnelling under the Brisbane River and CBD; four new underground stations constructed at Boggo Road, Woolloongabba, Albert Street and Roma Street; and the upgrade of the existing Dutton Park and Exhibition stations.

Labor’s pledge would send $800 million into building the line, with the remaining money to fund a 50-50 split of its running costs with the state government.

“This is south-east Queensland's number one infrastructure project – that's why Labor is making it a priority,” opposition leader Bill Shorten said in a statement. “This will allow more trains, more often. It will take cars off the road and get traffic moving.”

The state Labor government had previously pledged to fund CRR on its own if necessary, committing almost $3 billion over four years with the remainder to be included in future budgets.

The Palaszczuk government today welcomed the announcement by Shorten, with deputy premier and treasurer Jackie Trad noting it means Queensland won’t have to go it alone if the project succeeds.

“Cross River Rail is essential to the future of transport in the whole south-east region and we need to build it now,” she said in a statement. “That’s why the Queensland Government committed to fully fund the project on our own, after years of being ignored by the Turnbull LNP government.”

Shorten’s announcement will put pressure on the Coalition government, with Labor also committing to match Malcolm Turnbull’s $1 billion pledge to widen two sections of the M1 – meaning that project will go ahead no matter who wins the next election.